1. Field of the Invention
The present field of the invention is related to a reticle POD, and more particularly, to the structure of a reticle POD disposed with a plurality of supporting components.
2. Description of the Prior Art
In modern advanced Foundries or semiconductor Fabs, the level at 90 nm and below process has been achieved in the chip manufacturing process; therefore, the size of pattern on the reticle for lithography process has to be reduced and the width of lines in the pattern needs to be small, and the production cost is thus very high. In order to reduce the high production cost of reticle, modern advanced Foundries or Fabs, especially Foundries or Fabs manufacturing memory products, manage to increase the lifetime of reticle.
Due to needs in the manufacturing process, it is often needed for the reticle to be transferred to and fro between the storage box and the lithography tool. Therefore, the reticle needs to be stored in the reticle POD so that the reticle can be prevented from being contaminated by particles. As the reticle POD needs to be transferred, two concerns thus arise in regard to the process of placing the reticle into the POD: first, the reticle has to be securely mounted so that the reticle will not be damaged due to friction between reticle and POD or between mounting blocks and supporting components caused by ineffective mounting of the reticle; second, the area of the reticle in contact with the mounting blocks or the supporting components has to be reduced in order to reduce the electrostatic effect caused by friction, and more particularly, the contact area is to be limited to the peripheral area of the reticle without pattern so that damages caused by contact or friction between reticle and mounting blocks or supporting components can be avoided. Many patents have thus disclosed designs of supporting components for mounting the reticle. For example, as shown in FIG. 1, Taiwan patent 1227210 discloses structure and deployment of supporting components in a reticle POD. Wherein when the reticle is placed in the reticle POD, only peripheral area of the reticle is in contact with the bevel of supporting components. However, there are two defects in the design of the supporting components. One defect is that the supporting components are fixedly integrated with the reticle POD and each supporting component has a rigid body and lacks cushion-like property. Thus when the reticle POD is dashed or falls down, the impact force will pass through the supporting components and directly to the reticle and may cause partial damage or shattering of the reticle. The other defect is that the design of individual supporting component makes it easier for the reticle to be displaced and thus damaged when the reticle is placed into the POD due to lack of proper leading device.
Therefore, the supporting components need to be designed as having elastic property to effectively reduce the damage of reticle caused in the transferring or storing processes. Moreover, design of effective leading device is also necessary so that the reticle can be automatically led to the position for mounting when being placed into the reticle POD. To achieve the aforementioned, the present invention provides a supporting component structure equipped with elastic property at the area in contact with the reticle and with leading elements for the reticle to be precisely placed into the position for mounting. Furthermore, due to the advancement of the process, in the processes of higher level in Fabs, EMI in Fabs, in addition to electrostatic effect, will also cause damage to the reticle, particularly when the reticle is in the stage of being stored or in the lithography process and changes in the surroundings are hard to predict. Thus, in consideration of possible damages that may be caused by ESD and EMI and need to be prevented, the present invention also provides an embodiment of reticle POD made of metal in addition to reticle POD made of polymer material. Not only can the reticle in the metal reticle POD be effectively mounted and isolated from air, the metal reticle POD can also prevent the reticle from being damaged by ESD and EMI.